Mineralogical Techniques for Investigation of Solidified/Stabilized Organic Wastes

Solidification is mainly used to improve the physical properties of waste like compressive strength and permeability. The aim of solidification concerning pollutants is stabilization. That means to limit the solubility or to detoxify any hazardous constituent of the waste e.g. by sorption, pH-adjustment or change of chemical binding properties. Both terms together are used to describe the treatment processes (solidification/stabilization techniques). For the prediction of the long term behaviour it is necessary to include informations about the mechanisms of stabilization as well. Mineralogical methods like X-ray diffraction analysis (XRD), Scanning electron microscopy (SEM) or Transmission electron microscopy (TEM) can help to get these informations. Such methods are known and commonly used for investigating solidified/stabilizied waste containing heavy metals [1,2,3]. However only little knowledge exists on the characterization of solidified/stabilized organics by these techniques [4]. In this investigation we characterized solidified/stabilized organicslusing mineralogical methods. This research were part of a project on the remediation of the sanitary landfill in Hamburg-Georgswerder [5]. A model oil designed to simulate the composition of a typical oily waste was solidified by different inorganic as well as organic binders (e.g. cement, lime, gypsum, bitumen, Trinidad asphalt) and fillers (e.g. chalk, lignite). Both the raw material and solidification products were studied by XRD analysis and SEM.